1. Field of the Invention
The present invention relates to a linear compressor, more particularly, to a muffler of the linear compressor, in which a center of an entry pipe of the muffler is in line with that of an inhale port of a piston, whereby the linear compressor has an effect on reducing a flow loss occurred when fluid is inhaled into the inhale port from the entry pipe.
2. Description of the Related Art
Generally, a linear compressor is a machine to inhale, to compress, and to discharge fluid by linearly reciprocating a piston within a cylinder, by means of linear driving force of a linear motor.
FIG. 1 shows the linear compressor based on the prior art, FIG. 2 shows a muffler of the linear compressor based on the prior art, and FIG. 3 shows a sectional view taken on line A-A of FIG. 2.
The linear compressor according to the prior art, as illustrated from FIGS. 1 to 3, comprises a hermetic casing 2 having an inlet 1 where fluid is entered from the outside, and a linear compression part 10 placed in the hermetic casing 2 to compress fluid.
The linear compression part 10 includes a cylinder block 12 having a cylinder 11, a back cover 14 having an inhale pipe 13, a piston 15 mounted in the cylinder 11 to reciprocally move back and forth, and the linear motor 20 which generates driving force to allow the piston 15 to linearly reciprocate in the cylinder 11.
The cylinder block 12 and the back cover 14 are upheld in the hermetic casing 2 by a main damper 26 and a subsidiary damper 27, so as to absorb a shock.
The linear motor 20 is divided by a stationary part and a movable part. The stationary part includes an outer core 21, an inner core 22 disposed at a regular interval with the outer core 21, and a coil 23 with a magnetic field. The movable part includes a magnet 24 arranged between the outer core 21 and the inner core 22 to linearly reciprocate by magnetic force around the coil 23, and a magnet frame 25 fastened to the magnet 24 and combined with the piston 15 to transmit linear driving force to the piston 15.
The piston 15 has a flange 16 fixed to the magnet frame 25. A main spring 28 is elastically suspended between the flange 16 and the cylinder block 12, and a subsidiary spring 29 is elastically suspended between the flange 16 and the back cover 14.
The piston 15 is provided with an inhale passage 17 where fluid is flowed in, a plurality of inhale ports 18 in front, and an inhale valve 33 to open and close the inhale port 18.
An exhale part is formed in a front of a compression chamber C of the cylinder 11, where compressed fluid is discharged. The exhale part includes an inner exhale cover 34 fixed to the cylinder block 12 and provided with an exhale hole, an exhale valve 36 suspended to the inner exhale cover 34 by the spring 35, so as to open and close the compression chamber C of the cylinder 11, and an outer exhale cover 37 positioned at a regular interval from an outer surface of the inner exhale cover 34.
The outer exhale cover 37 is linked with a loop pipe 38 which guides discharged fluid to the outside of the hermetic casing 2.
The muffler 30 is installed between a back of the piston 15 and the inhale pipe 13 of the back cover 14, so that an inhale noise is mitigated.
Referring to FIG. 2, the muffler 30 comprises a muffler body 31 where the inhale pipe 13 is inserted and a plurality of resonance spaces is configured to reduce the noise, and an entry pipe 32 configured in a long length within the inhale passage 17 of the piston 15, so as to inflow fluid.
The conventional linear compressor operates in the following sequence.
In operation of the linear motor 20, the piston 15 has linearly reciprocating motion within the cylinder 11. Fluid in the hermetic casing 2 is inhaled into the inhale pipe 13 of the back cover 14, is compressed within the cylinder 11 by the piston 15, and is discharged outside from the exhale part and the loop pipe 38.
Here, fluid is inhaled through the inhale pipe 13 of the back cover 14, prior to being inhaled into the inhale passage 17 of the piston 15 after going through the muffler 30. Fluid inhaled into the inhale passage 17 of the piston 15 is flowed into the compression chamber C through the inhale port 18 of the piston 15 by opening the inhale valve 33 when the piston 15 is backed. Fluid contained in the compression chamber C is compressed by closing the inhale valve 33 when the piston 15 is advanced.
However, in which the linear compressor having the conventional muffler, the inhale port 18 of the piston 15 is eccentrically situated in a front of the piston 15, the entry pipe 32 of the muffler 30 is formed toward a center of the piston 15, and a center of the inhale port 18 and that of the entry pipe 32 are out of line each other. When fluid is inhaled into the inhale port 18 from the entry pipe 32, a flow loss is suffered and inhale efficiency is deteriorated.